Migrate Grafana dashboard definitions from Grizzly to grafanactl

[markuslf]

Grafana is phasing out Grizzly in favor of grafanactl (see grafana/grafanactl#97). This requires migrating all dashboard YAML files.

Current state

All dashboard YAMLs use the Grizzly format:

apiVersion: grizzly.grafana.com/v1alpha1
kind: Dashboard
metadata:
  folder: linuxfabrik-monitoring-plugins
  name: example
spec:
  # ...

Continue using this format until the migration is complete.

Target format

grafanactl uses a Kubernetes-style resource format:

apiVersion: dashboard.grafana.app/v1
kind: Dashboard
metadata:
  name: example
  namespace: default
spec:
  # ...

Key changes:

• apiVersion: grizzly.grafana.com/v1alpha1 → dashboard.grafana.app/v1
• metadata.folder → metadata.namespace
• The spec block (panels, targets, field configs) stays the same

Requirements

• grafanactl requires Grafana 12+
• grafanactl is currently in public preview, not yet production-ready
• YAML files should only contain properties that differ from Grafana defaults (no boilerplate, no default values)

Scope

• Migrate all check-plugins/*/grafana/*.yml files to the grafanactl format
• Update tools/ if any tooling generates or validates Grafana YAMLs
• Update CONTRIBUTING.md to reflect the new format
• Verify all dashboards import correctly via grafanactl resources push